Multi-step anodization of nanoporous TiO2 from electropolished titanium foil
Abstract
The present study reveals the development of titanium oxide (TiO₂) nanoporous array by two-step anodization of Ti foil in ethylene glycol solution containing NH4F (0.3 wt%) and H₂O (1.0 wt%). The influence of electropolishing and anodization steps on the surface of the Ti substrate was investigated in producing defined and uniform nanoporous structure. SEM micrographs confirm the pore size, growth, and uniformity of the formed TiO₂ nanopores. An AFM image shows a well defined hexagonal concave structure which acts as nucleation site for uniform growth TiO₂ nanoporous array prior final anodization step. Crystal structure of the form TiO₂ layers were investigated using XRD analysis.